Zircon or zirconite is a gemstone, a nesosilicate mineral and owes its name to the Arabic word zirgun. It occurs in metamictic phases mainly in rare earth metals and is the only stone that competes the diamond both in terms of shine and the other properties (clarity, cut, etc.)
Pearls are lustrous and hard organic gems formed within mollusks, mainly in shells, around an original core, which can be either a parasite or a grain of sand. These foreign particles are then coated with layers of calcium carbonate. Pearls are thought to ward off negativism and clarify emotions. In the Apocalypse of John, pearls adorn the gates of the New Jerusalem.